A “wireless hotspot” is commonly known in the art as a geographic location, such as a coffee shop, cafe, airport lounge, hotel lobby or other populated location, where a public wireless network service is provided to “roaming” users of wireless mobile terminals (MTs) through a wireless network, to gain access to the Internet or other networks. The wireless network service is provided by a wireless access point (AP) that serves as an entry point through which the user's MT can get access to the Internet. “Getting access” here means the user can set up data connections to his communication peers on the Internet, and the user's MT can send or receive data packets to or from these peers. It also means that the user can enjoy various Internet applications such as email, messaging, web browsing, multimedia, voice, audio, image, video, file transfer, download, upload, or sharing enabled by these data connections and their data flows.
In such a public wireless hotspot, a roaming user with a MT may be within wireless range of multiple APs. Before the MT can select the AP most appropriate for the user, the MT should discover and consider one or more types of service information. The most critical type of service information is roaming information, i.e., information about whether the AP has a roaming agreement with a network service provider of the user. Other information types that may be useful for the MT to discover and consider include, without limitation, security policies, price, and AP workload.
In view of the foregoing, a method for discovering service information is critically needed. The method should be scalable and backward compatible, it should not require technology changes, it should not require association before discovery of the information, and it should not hinder fast handoff.